(Sarah Parnass,Dani Player/The Washington Post)

A massive blast tore through the diplomatic quarter of the Afghan capital Wednesday, killing at least 80 people and wounding more than 460, officials said. The devastation left Kabul in shock and underlined the country’s security struggles as it confronts a sustained wave of insurgent and terrorist attacks.

Interior Ministry officials said a huge quantity of explosives, hidden in a tanker truck, detonated at 8:30 a.m. during rush hour on a busy boulevard in the Wazir Akbar Khan district, which houses embassies, banks, supermarkets and government ministries. An entire city block was ravaged, with office buildings left in rubble and charred vehicles strewn across the road in one of the deadliest single attacks in Kabul.

The scenes of human horror were appalling, even for a country accustomed to war and violence.

At Wazir Akbar Khan Hospital, a steady stream of ambulances and police trucks delivered burned and mangled bodies, many streaming blood. Medical aides struggled to zip them quickly into body bags as distraught people crowded around, looking for missing relatives.

“I felt like it was an earthquake, and after that I do not know what happened,” said Mohammed Hassan, 21, who was attending a training program at the Azizi Bank, a half-block from the blast, and suffered cuts on his head and arms. “All the staff around me, everyone, was injured.” He said he was brought to the hospital by an Afghan army ranger truck. 

The dead and wounded were almost all Afghan civilians and security forces: police officers, bank clerks, cart pullers, telephone company workers. The dead included at least five women, an Afghan driver for the BBC and at least nine Afghan guards stationed at points outside the U.S. Embassy.

Although many foreign offices are nearby — many surrounded by high blast walls — there were no reports of foreigners among the fatalities. But some workers in diplomatic compounds, including those of Japan and Germany, were among the injured.

At least 11 U.S. citizens working as contractors also were injured, a State Department spokesman said.

The Afghan Taliban denied any role in the bombing, which was followed by a second, smaller blast in another part of the city. The Taliban spokesman, Zabiullah Mujahid, did not speculate on which group could have carried out the attacks but said it should “become clear at a later stage.”

Security agencies had warned that Taliban insurgents and regional affiliates of the Islamic State were planning to attack high-profile targets in the city in the early part of Ramadan, the Muslim holy month that began last week.

Many injured survivors were cut by shards of glass from storefronts, offices and foreign compounds — as far away as several miles from the main blast site. By midmorning, many were limping or being wheeled out of local hospitals, with their clothes covered in blood and their heads, arms or feet wrapped in bandages.

Nearby, distraught families squatted around bloody body bags, guarding them in patches of shade.

Relatives of Afghan victims mourn outside a hospital after a blast in Kabul. (Omar Sobhani/Reuters)

There were muffled, choking sounds of men weeping. Most of the dead had been seared by the blast; some were wrapped in cloth but others were half-naked and dripping blood. The Afghan Ministry of Public Health placed the death toll at 80 and the injury count at 463.

“What will I tell his children?” a sobbing man said into a cellphone as he knelt beside a bag containing the remains of his brother, a guard in a building near the explosion. 

“Look, that one is a woman. Shame, shame,” said an elderly man, pointing to a stretcher with a slender body wrapped in cloth and a hank of long hair dangling outside.

Afghan President Ashraf Ghani’s government issued a statement condemning the blasts as “heinous acts that go against the values of humanity as well [as] values of peaceful Afghans.” It also said the attacks “demonstrate the extreme level of atrocity by terrorists against innocent civilians.”

A statement from NATO forces in Afghanistan praised “the courage of Afghan Security Forces, especially the police and first responders.”

“Attacks such as these only serve to strengthen our commitment to our Afghan partners as they seek a peaceful, stable future for their country,” the NATO statement added.

There are 8,000 U.S. troops in Afghanistan supporting the government, but earlier this year, Gen. John Nicholson, the top U.S. commander there, said he needed several thousand more to break the stalemate. The U.S. Embassy is about a half-mile from the blast site, but at least nine Afghan guards died in the blast, the State Department said.

Public anger at the Afghan government built during the traumatic hours after the blast. People with grim, dazed faces­ strode along the sidewalks, avoiding piles of glass, or sat glumly in modern offices with all their windows gone, watching the news on TV.

“This is an inept government that cannot protect the people and must be dissolved. It is time for an interim government to be formed,” said Mirwais Yasini, a member of parliament.

The Ghani government, weakened by internal tensions, has faced an uphill battle to fend off an aggressive push by Taliban insurgents in recent months, as well as a number of assaults claimed by the Islamic State.

Others expressed disgust for the attackers, especially since they chose Ramadan, a period that Muslims devote to prayer and fasting.

Wounded men lie on their beds in Wazir Akbar Khan Hospital. (Massoud Hossaini/AP)

“How can the people who did this call themselves Muslims?” demanded Ahmed Mohibzada, 24, an office worker who had walked to the Wazir Akbar Khan Hospital to donate blood after hearing of the massive number of injured survivors.

He was lying on a gurney in the hospital porch with his sleeve rolled up. “I just felt I had to do something,” he said.

Others wept in frustration when they scanned lists of injured patients on the hospital wall and could not find the name they were looking for. One man pounded angrily on the hospital’s front door, arguing with the guard.

A woman ran through the crowd, shouting hysterically. “My son is a good Muslim. I have to find him,” she shrieked over and over, long past caring who was listening.

The diplomatic zone in Kabul is among the city’s most highly protected. Yet attackers have managed to breach its security in the past.

In 2015, suspected Taliban gunmen rampaged through the area, engaging in an overnight gun battle with security forces. The four attackers were killed, but there were no civilian casualties.

Brian Murphy in Washington contributed to this report.